Pulsed control circuit

ABSTRACT

The disclosure includes a radio-controlled garage door operator, operated from a pulsed latch relay connected to be energized by a pushbutton switch or contacts of a pulsed relay of a radio control receiver unit. The latter includes a superregenerative, self-quenching oscillator receiver connected to a channel selection and demodulating circuit. The selection circuit includes a paralleled resistor and capacitor in series with a diode to pass the desired door-operating frequency signal and actuate an electronic switch. A bypass circuit includes a parallel capacitor and adjustable inductor in series with an attenuating circuit including a paralleled resistor and capacitor. The inductor-capacitor resonates at the door-operating frequency. The output circuit includes a pair of complementing normally off transistors interconnected by a timing and disconnect capacitor. The first transistor is driven on and provides a turn on bias path for the second transistor including the capacitor to momentarily actuate the latch relay. The capacitor is maintained charged through an alternate path which when the first transistor turns off provides a rapid discharge capacitor path. The receiver circuit is connected to the power supply through the same contacts connected to actuate the relay and thereby provides a two-wire control connection.

United States' Patent- Alphons E. Bachhuber, Jr. Primary Examiner-Robert L. Griffin 1 Appleton, Wis. Assistant Examiner-Kenneth W. Weinstein [2!] Appl. No. 838,290 AttorneyAndrus, Sceales, Starke & Sawall July 1, 1969 Dec. 28, 1971 Advance Industries, ABSTRACT: The disclosure includes a radio-controlled Appkmn, garage door operator, operated from a pulsed latch relay connected to be energized by a pushbutton switch or contacts of a pulsed relay of a radio control receiver unit. The latter includes a superregenerative, self-quenching oscillator receiver connected to a channel selection and demodulating circuit. The selection circuit includes a paralleled resistor and capacitor in series with a diode to pass the desired door-operating frequency signal and actuate an electronic switch. A bypass circuit includes a parallel capacitor and adjustable inductor in series with an attenuating circuit including a paralleled resistor and capacitor. The inductor-capacitor resonates at the door-operating frequency, The output circuit includes a pair [72] inventor [22] Filed [45] Patented [73] Assignee [54] PULSED CONTROL CIRCUIT 8 Claims, 1 Drawing Fig.

[52] US. Cl

- H04, 1/16 of complementing normally off transistors interconnected by a 5 11 1m. I [50] Field of timing and disconnect capacitor. The first transistor is driven on and provides a turn on bias path for the second transistor including the capacitor to momentarily actuate the latch relay. The capacitor is maintained charged through an alternate path which when the first transistor turns off provides a rapid [56] References Cited UNITED STATES PATENTS 3,359,558 12/1967 Schanbacher..........,.....

discharge capacitor path. The receiver circuit is connected to the power supply through the same contacts connected to actuate the relay and thereby provides a two-wire control connection.

4/1969 Leland 5/1969 Goldstein 8/1969 Barlow PULSED CONTROL CIRCUIT BACKGROUND OF INVENTION This invention relates to a triggered load control circuit and particularly to a remote radio-type control system, such as radio-controlled garage door operators and the like.

Various remote control systems have been suggested for controlling of a load spaced from the actual control for such load. Remote radio controlled systems have been developed for garage door control and the like, wherein the door is raised and lowered by a motor. A switching means is provided for selectively applying power to the motor with a self-cyling turnoff device to open the power circuit when the door is totally opened or closed. For example, a two-position relay may be connected to selectively supply power for raising of the door to one position and for lowering of the door in the opposite position. Each of the respective raising and lowering circuits includes a limit switch which is opened when the door is in the corresponding position. Each pulsed operation of the relay causes it to move from the then-opened circuit to the opposite circuit, providing power to the motor until the related limit switch opens. The triggering circuitry will normally include a manually operated pushbutton switch for controlling the load from the adjacent portion of the building. For remote driver control a radio receiver is provided having relay or other similar switch means connected in parallel with the pushbutton switch for simulating the actuation of the pushbutton. In radio-controlled receivers and the like, each receiver must, of course, be related to a particular frequency in order that the garage door is not operated by signals generated from unauthorized transmitters; particularly where the driver may operate his door at a reasonably long distance from the garage door to avoid undesirable delays. For example, a substantial number of garage door operators might be placed in a given subdivision of homes where the several door operators are mounted in relatively closely spaced relationship. The operating range is normally such that the signal transmitted from any one transmitter for operating its receiver will also apply a sufficient level signal to the adjacent receivers, which, if not set to reject such signal, will result in the unauthorized, operation of such other receivers. Further, as the garage door operators and the like can only operate within a certain frequency band, the provision of a very sensitive selection circuit is of substantial practical significance, particularly for subdivision application and the like where a substantial number of units are to be installed in relatively close relationship.

The receiver may advantageously be constructed using an oscillator detection means to provide a high degree of sensitivity. However, care must be taken to minimize the radiation of radiofrequency energy in order to comply with the standards established by governmental agencies. The prior art remote controls and the like generally employseparate power connections for the receiver and for the motor operator. It would, of course, be desirable to provide a single two-wire power supply for supplying energy to the load circuit and to the receiver.

SUMMARY OF INVENTION The present invention is particularly directed to a radiocontrolled unit having a selection circuit establishing a very narrow frequency response band and thereby permitting construction of a substantial number of the receivers each operating at a different frequency within an allotted frequency range. Generally, in accordance with the present invention, a receiving and detecting circuit, preferably a superregenerative self-quenching oscillator receiving circuit, amplifies the incoming tone frequency signal for operating of the receiver. The amplified signal is applied to a special channel selection and demodulating circuit which is constructed with a very sharp or narrow frequency transmitting band and which reliably transmits only the desired frequency for which the particular receiver and operator is to respond. Generally, in accordance with the present invention, the channel selection circuit includes a band-pass circuit, such as a paralleled resistor and capacitor, connected in series with a diode between the output of the superregenerative oscillator and detector and a final amplifying stage. This circuit will pass the tone signal to which the particular circuit is to respond. To limit the response to a given frequency, a bypass circuit is provided including a first resonant circuit formed by a parallel capacitor and inductor. The bypass circuit further includes a paralleled attenuating circuit, such as a paralleled resistor and capacitor, connected between the tune resonant circuit and the common side of the circuit. The resonant circuit is adjusted to resonate at the particular frequency to which the operator is to respond. The high frequencies and other tone frequencies are, therefore, off resonance. The high frequencies such as the quench frequency will therefore be passed by the tuned circuit and attenuated by the parallel capacitor and resistor as a result of the high reactance of the capacitor to this relatively high frequency. When an incoming operator control signal is received, a tone-modulated transmitter signal is amplified by the regenerative oscillator and detector and transmitted with other frequencies to the selection circuit. The signal will generally include some of the quench frequency signal as well as the tone frequency. If the tone frequency received is different than that to which the resonant circuit is tuned, this tone signal also passes the resonant circuit as a lowest impedance path. In accordance with another aspect of the present invention, the opposite polarity half cycle from that employed to drive the receiver may be rectified and applied to the output stage as an inhibitor, thereby positively insuring that the receiver is driven off the bandpass of the circuit may be controlled by proper selection of the values of the various resistors and capacitors, as well as the Q of the resonant circuit coil.

The output circuit of the receiver in accordance with another aspect of the present invention is a rapid acting or pulsed switching circuit. The circuit includes a pair of complementing transistors interconnected to define a complementing two-stage amplifier. The load is connected in series in the second stage and controlled by the first stage. The circuits are interconnected by a timing and disconnect capacitor. When the first stage is driven on, it provides a turn on bias path for the second stage including the tumoff capacitor. This provides energy to the output means, such as relay winding. The capacitor charges and turns off the second stage, thereby, deenergizing the relay and providing in essence a momentary energization thereof. The capacitor is maintained charged through an alternate path which when the first stage turns off provides a rapid discharge path for the capacitor and a rapid resetting of the circuit. With this system, the circuit will maintain the last-established condition, as long as the original turn on signal appears. However, if the original signal is removed, the system will rapidly reset such that a subsequent signal will reverse the output condition or establish another output. A continuous signal is not effective to hold the output means in a latched or triggered condition and cannot override a safety switching system such as widely employed in garage door motor control circuits. However, if the operator wishes to reverse the movement of the door-for any reason, the release of the signal resets the system such that the next actuation of the control is effective to immediately reverse the circuit for the door operator motor.

The present invention employs a load system, wherein continuous power must be supplied to the radio-control circuit as a load and momentarily to the operator triggering circuit as a load. To minimize the installation and maintenance, a simple two-wire connection is desired. In accordance with another aspect of the present invention, the rapid-acting switch means provided by the pulsed energization of the relay or the like provides a system wherein the operatively continuous power is supplied to the one load while providing a momentary or pulsed actuation of a second load over a single pair of conductors in a reliable and inexpensive manner.

The present invention thus provides an improved control circuitry, particularly for responding to a given radiofrequency signal, and in particular, wherein it is desired to simultaneously provide continuous power to a pair of circuits, and simultaneously provide for a pulsing signal to the one circuit.

BRIEF DESCRIPTION OF DRAWINGS The drawing furnished herewith illustrate the best mode presently contemplated by the inventor for carrying out the subject invention and clearly discloses the above advantages and features as well as others which will be readily understood from the following description of the illustrated embodiment of the invention.

The drawing is a schematic circuit diagram of a radio-controlled garage door operator constructed in accordance with the present invention.

DESCRIPTION OF ILLUSTRATED EMBODIMENT In the drawing, a garage door 1 is diagrammatically illustrated which may be opened and closed by an automatic garage door operator 2. The garage door 1 is mounted in the usual manner and is interconnected through a suitable chain drive 3 or any other suitable coupling means to an opening and closing motor 4. The motor 4 is illustrated as an alternating current motor which may be connected to the usual 120- volt alternating current power supply line 5 such as conven-' tionally available in the United States. In the illustrated em bodiment of the invention, the operator 2 is adapted to be controlled manually from a pushbutton switch unit 6, the momentary actuation of which completes the circuit of the operator 2 for purposes of energizing the motor 4 to raise or lower the door 1. Alternatively, the operator is adapted to be remotely controlled through a relay 7, having a pair of contacts 74 connected in parallel with the pushbutton switch unit 6. The relay 7 is connected in the output circuit of a remote radio-control circuit 8 having a suitable input antenna 9. As more fully developed hereinafter, when a suitable tone frequency signal is received at the antenna 9, the relay 7 is momentarily energized with a resulting corresponding closure of the contact 7-1. This results in a corresponding actuation of the operator 2 to raise or lower the door 1. Generally, the illustrated radio-control circuit 8 includes an R-F amplifier l0 interconnected to the antenna 9 to receive the incoming control signal and to provide amplification thereof. The amplified signal is applied to a superregenerative self-quenching oscillator and detector circuit 11. This combination provides a very sensitive response to the incoming signal, while minimizing the 'radiation associated with the oscillator receiver. The output of the oscillator circuit 11 is connected to a two-stage amplifier 12 to increase the level of the incoming signal. As a practical matter, the amplifier 12 will also transmit and amplify the quench frequency component of the oscillator circuit. The amplified signal is applied to a special channel selection and demodulating circuit 13 which is operative to transmit a desired tone frequency signal and to effectively bypass all signals of a different frequency. The output of the circuit 13 is applied to a final output power and switching circuit 14 which is adapted to provide momentary energization of the relay 7 in response to transmission of the selected tone frequency signal.

Generally, the radio control circuit 8 is provided with bias power from a half-wave filtered DC power supply 15 interconnected into driving power from the circuit of the operator 2 through a set of common input power conductors 16 which also supply and connect the contact 7-1 in parallel with the pushbutton contact 6. As more fully described hereinafter, this provides a highly desirable two-wire power supply system for a radio-controlled door operator or any other system requiring constant power supply in combination with a momentary switching.

The oscillator circuit 11 is provided with a variable inductance 17 to permit radiofrequency tuning of the oscillator circuit 11. In the illustrated embodiment of the invention, the

R-F amplifier l0 and the oscillator circuit 11 will generally be readily understood by those skilled in the art and no further detailed description thereof is given. The R-F amplifier l0 and the superregenerative self-quenching oscillator circuit 11 has been found to provide a highly desirable response and sensitivity, which in combination with the special channel select and demodulator section, which is operative to restrict the transmission of the received signal to the desired tone frequency, produces a sensitive and reliable radio-controlled operator.

The two-stage amplifier employs a pair of similarly connected NPN-transistors l8 and 18', shown interconnected in a common emitter configuration to the bias supply 15. In each of the stages, the input circuit to the transistor 18 and 18' similarly includes a capacitor 19 and l9', respectively, to ground.

The capacitors l9 and 19' are effective to bypass some of the quench frequency and noise frequency components of the signal to ground, and thereby reduce the corresponding signal components which must be removed by the channel selection and demodulator circuit 13.

The channel selection and demodulator circuit 13 forms a significant part of the present invention, particularly when combined with superregenerative and preamplifying module to produce a highly sensitive reliable radio-controlled operator. Generally, the channel selection circuit is a narrow bandpass circuit coupled through a capacitor 20 and a series resistor 21 to the output of the amplifier 12. A resonant circuit 22 is connected to the resistor 21 for purposes of selectively bypassing the high frequency and tone frequency other than that selected for operation of the particular operator 2. The resonant circuit 22 includes a variable inductor 23 having an adjustable iron core diagrammatically shown by the arrow 24. The inductor 23 is connected in parallel with a capacitor 25 to define the usual L-C resonant circuit. The inductor 24 is adjusted such that the circuit will be resonant at the operating tone frequency for the particular operator 2. It thereby establishes a high impedance for that frequency and a relatively low impedance for all other frequencies. A high-frequency attenuating circuit 26 is connected between the resonant circuit 22 and the common or ground lead of the circuit. The attenuating circuit 26 includes an attenuating capacitor 27 connected in parallel with a suitable resistor 28. The highfrequency quench signal and the like are passed by the resonant circuit 22 and attenuated by the reactance of the capacitor 27 to the highfrequency signals.

A tone frequency transmitting circuit 29 is connected between the resistor 21 and the input to the switching circuit I4. The circuit 29 includes a capacitor 30 connected in parallel with a resistor 31. The paralleled elements are connected in series with a diode 32 between the resistor 31 and a common output lead 33, which is interconnected as the input to the amplifying and switching circuit 14. If the received tone frequency signal corresponds to that for the particular operator, which in turn is determined by the setting of the inductor core 24, the resonant circuit 22 becomes a high impedance to that portion of the signal. As a result, that portion of the signal is passed through the parallel transmitting circuit 29, rectified by the diode 32 and applied at the output lead 33 as a properly polarized rectified signal which functions to produce the desired switching action, as hereinafter described.

, If the received signal includes a tone frequency in the range employed for the operators, but different'from the resonant frequency established by the resonant circuit 22, this signal will also pass with the quench frequency component and the other high-frequency components through the resonant circuit 22 as a lowest impedance path.

In the illustrated embodiment of the invention, an inhibiting branch circuit 34is connected between the resonant circuit 22 and the common output lead 33. The inhibiting circuit includes a diode 35 in series with a resistor 36. The diode 35 is connected with respect to the incoming resistor 21 and lead 33 of polarity which is the opposite of the diode 32. A tone frequency signal, which is different than that of the selected operating frequency passes the resonant circuit 22 and the negative or opposite half cycle is half-wave rectified by the diode 35 to produce a signal at line 33 of an opposite polarity from that produced via the circuit 29 and diode 32. The opposite polarity signal at the common output lead 33 produces an input to positively hold off the amplifying and switching circuit 14.

The bandpass of the channel selection circuitry may be controlled by the selection of the particular values for the several resistors and capacitors as well as the Q of the inductor 23. In a practical application, the circuit was constructed with the components other than that of the resonant circuit 22 of a selected value. Several inductors having differing number of turns were connected to establish various tone frequency band-pass ranges, and to permit adjustment within such range to a particular tone signal frequency. Generally, the several tone frequency signals were adjusted .to differ by 1,000 Hertz. In particular, in a practical construction the following components were employed:

Resistor 21 33K 54 watt lO'I: Allen Bradley Resistor 31 lOOK 56 watt 5% Ampere:

Resistor 28 lOK 54 watt Amperex Resistor 36 22K 54 watt 5% Ampere:

Capacitor 27 200PF Disc or 470PF-JF Series or Capacitor 30 0.0l Disc Diodes 32, 35 IN 774 Rubinstein The resonant circuit 22 was constructed with four different ranges, each of which was adjustable to two or more different tone signal frequencies, as follows:

Inductor Turns Slug Capacitor (u.f.) Resonant (kHz.)

3,600, No. 38 wire 5 0.0039 6 l A inches 1,600, No. 34 wire 1% inches l,000, No. 34 wire H4 inches The circuit of the invention thus may provide a very substantial number of different operative control signals such that the operator within a given area without danger of actuating more than the desired operator, as a result of transmitting the operating signal. As previously noted, such a system becomes a very substantial significant in connection with garage door operators, where a very substantial number of the units may be placed in relatively closely spaced relation; for example, in a subdivision of homes. The frequency range for garage door operators will normally cover the range of 5 to kilohertz (kHz). As a practical matter, however, for other applications the frequency may be selected anywhere within the audio range up to and including approximately 100 kHz by proper adjustment of the resonant circuit and selection of the attenuating capacitor and the tone signal passing capacitor.

The signal appearing at the line 33 is applied to the power amplifying and switching section 14. The illustrated circuit 14 provides a rapid switching action and generally includes a pair of complementing transistors 37 and 38 interconnected to the bias supply 15 such that both transistors are off. The illustrated transistor 37 is an NPN-type connected in a common emitter configuration with the base connected to the line 33 and to the common supply lead through a paralleled input resistor 39 and capacitor 40. A load resistor 41 is connected in the collector circuit which in turn is coupled through a timing and 13 control capacitor 42 to the base 43 of the output or second-stage transistor 38. The transistor 38 is a complementing or PNP-transistor also connected to the power supply 15 in a common emitter configuration with the relay 7 connected in the collector circuit. An input resistor 44 is connected between the positive side of the power supply 15 and the base 43 of the transistor 38. In the standby position both the transistor 37 and the transistor 38 are biased off. A positive voltage of a sufficient amplitude applied across the input resistor 39 and capacitor 40 from line 33 to ground biases the transistor 37 to conduct. When the transistor 37 conducts, it effectively grounds the collector-connected side of the capacitor 42 and provides a current path through the resistor 44. This, in turn, applies a turn on bias to the transistor 38, which then conducts, energizing the relay 37. The transistor 38 is biased on until such time as the capacitor 42 charges to a cutoff voltage, thereby terminating conduction through the transistor 38, even though transistor 37 remains conducting. This then establishes a momentary or pulsed energization of the relay 7 with the relay contact 7l momentarily closing to simulate the actuation of the pushbutton switch 6 for operating of operator 2.

As long as the transistor 37 conducts, the capacitor 42 will maintain the charged condition even though the transistor 38 is turned off, as a result of the circuit through the resistor 44. When the incoming signal is removed the transistor 37 is biased off. The capacitor 42 now discharges through the resistor 44 and resistor 41. The resistors are selected to provide a relatively rapid discharge path to reset the circuit after removal of the transmitter signal. The circuit thus provides a rapid response both in initial triggering of the circuit as well as resetting of the circuit. This is highly desirable in order to permit successive operation of the circuit where necessary for safety reasons or the like. Thus, it may be desirable after initially triggering the circuit, for example, to lower the door to rapidly reset the operator and actuate it again to raise the door and thereby avoid damaging a person or object in the path of the door. The rapid one-shot operation of this circuit has been found to provide the desired operation while maintaining the built-in safety feature.

In the illustrated embodiment of the invention, a feedback resistor 45 interconnects the collector of the transistor 38 to the base of the transistor 37 to insure continued conduction in response to the initial turn on of the transistors 37 and 38.

Additionally, a capacitor 46 is shown connected across the relay 7. While the transistor 38 conducts, the capacitor 46 charges. When the transistor 38 turns off, the capacitor 46 will discharge through the relay 7 to maintain energization for a predetermined time and insuring the desired pulse energization of the relay 7.

In the illustrated embodiment of the invention, the relay contact 7-1 is particularly connected to the operator 2 in parallel with the pushbutton 6 via the common conductors 16, which supply the bias power to circuit 15. This is a particularly unique two-wire circuit connection providing a momentary pulsing and simultaneously providing essentially continuous operative power to the power supply 15.

In the illustrated embodiment of the invention, the one line 16 is connected to the common ground of the circuit. The one side of the relay contact 7-1 is also connected to this common lead. The opposite power line 16 is connected to the opposite side of the relay contact 7-1 and to the power supply 15. The connection to the power supply 15 is through a series connection of a diode and a resistor 47 to a filter network 48. A zener diode 49 is connected across the filter network to provide a predetermined constant DC power supply to the receiver circuit. When contacts 7-1 close, a direct short appears across supply 15. The rapid switching of circuit 14 and the timing of the relay energization is sufficiently rapid so that the power supply 15 of the receiver is not effectively disturbed or removed. As a result, the radio-control circuit 8 will continue to operate in the mode as previously described without repetitious relay operation, even though a continuous signal is applied from the transmitter to the receiver. Thus, the circuit will not reset during the period of momentary closure of the relay contact 7-1.

The illustrated operator 2 is generally a known type which has been manufactured and sold by the assignee of the present application. Generally, the operator 2 includes a triggering or latch relay 50 connected to the incoming power supply line 5 by a suitable stepdown transformer 51. The relay 50 is connected in series with the secondary of the transformer 51 and the parallel connected pushbutton switch 6 and the relay contacts 7-1. Thus, momentary closure of either the pushbutton switch 6 or the relay contacts 7, energizes the relay 50 to move the associated contacts. In the illustrated embodiment of the invention, relay 50 is a double-pole, double-throw relay having contacts alternately interconnected to energize the motor 3 for alternately raising and lowering door 1. The relay 50 includes a first contact pole or arm 51 connected directly to one side of the incoming powerlines 5. The ann 51 engages a first contact 52 in the full line position shown and an alternative contact 53 in response to the next energization 50. The relay 50 is constructed such that the momentary operation of the relay moves the contact arm 51 from its then-set position to the alternate position where the arm remains after deenergization of the relay.

The contact arm 51 is connected directly to the one side of the power supply. The contact 52 is connected in series with an up-limit switch 54 and a raising motor winding 55 of the motor 3. The opposite side of the motor winding 55 is connected by a lead 56 to the opposite side of the powerline. Thus, in the full line position shown, the garage door 1 had been raised and the limit switch 54 opened to tenninate the energization of the motor 3. Upon the next energization of the relay 50, either by the actuation of the pushbutton switch or closing of contacts 7-1, the contact arm 51 will move into engagement with the contact 53. The contact 53 is connected in series with a down-limit switch 57 which is now closed and a lowering winding 58 of the motor 3. The opposite side of the motor winding 58 is connected in common with the winding 55 by the lead 56 to the opposite side of the powerlines 5. Thus, the next operation of the circuit will result in the energization of the winding 58 and the rotation of the motor in a direction to lower the garage door 1.

The relay includes a second contact arm 59 which in the full line position shown is connected to the contact 53. In the alternate position, the contact arm engages a contact 60 which is connected directly to one side of the pushbutton switch 6. The contact arm 59 is connected in series with a normally open safety switch 61 and a normally closed safety switch cutout 62 to the opposite side of the pushbutton switch 6 and thereby provides an alternate energizing circuit for the relay 50. In the full line position shown, the contact arm 59 is connected to the contact 53, in this position the contact 53 effectively constitutes a dead contact for the contact arm 59. If the normally opened safety switch 61 is now closed for any reason, the relay 50 is again actuated, reverses the position of the contact arm 51 to the full line position shown. The motor winding 55 is now energized and the door 1 will be raised. The previously described action of capacitor 42 which turns ofi' transistor 38 after a definite time period therefore insuring the continuous operability, of the safety circuit and prevents the possibility of overriding the safety switch action in the circuit by maintaining a continuous tone frequency signal. However, the capacitor 42 rapidly discharges to reset the circuit when the signal is removed from transistor 37 and consequently, pennits rapid positive cycling of the operator 2.

The relay S0 is energized from the connecting powerlines 5 to the-stepdown transformer and particularly from the secondary thereof. Furthermore, the power to the receiver 8 is provided by the conductors 16 which also provide the circuit connection from the momentarily closed relay contacts 7-1. As a result, a single pair of connecting powerlines 5 is required to provide power to the operator 2 and to the radio-control unit In summary, the illustrated embodiment of the invention is constructed and operates as follows. The inductor 17 of the superregenerative self-quenching oscillator circuit 11 is tuned to the desired radiofrequency signal. The inductor 23 of the resonant circuit 22 in the channel selection and demodulator circuit 13 is tuned to a particular toned frequency as heretofore described. Power is supplied over the single pair of conductors 5 to supply continuous power to the radio-control circuit 8 and standby power to the relay 50 and the motor 3. If the antenna receives the tone frequency signal, it is suitably amplified by the R-F amplifier 10, the superregenerative circuit 11 and the two-stage amplifier 12 before being impressed on the channel selection and demodulator circuit 13. The capacitors l9 and 19' will tend to bypass some of the R-F signal, in the amplifying section 12. In the channel selection circuitry, the resonant circuit 22 provides a high impedance to the tone frequency signal, which is consequently transmitted via the capacitor 30 and resistor 31, rectified by 32 and applied as a rectified positive signal at line 33 to the switching circuit 14. The quench and noise frequency signals are bypassed through the resonant circuit 22 which provides a low impedance to these particular frequencies. The signalsare attenuated by the circuit 26 and particularly the capacitor 27.

The transmitted and rectified tone frequency signal drives the transistor 37 on, which in turn biases the transistor 38 on. The transistor 38 continues to conduct until the capacitor 42 is charged, at which time the transistor 38 turns off. The capacitor 46 discharges momentarily holding the relay 7 on. This results in the momentary or pulsed actuation of the relay contact 7-1 with a consequent corresponding energization of the latch relay 50. This reverses the position of the contact arms 51 and 59. In the illustrated embodiment of the invention, the motor 3 will then be energized to lower the door 1.

If for any reason, it is desired to terminate the lowering of the door, the transmitter can be again actuated to again establish a tone signal of the proper frequency which is picked up by the antenna 9, and after suitable amplification is passed through the channel selection and demodulating circuit 13 to again bias the transistor 37 to conduct. This results in the recycling of the circuit 14 with asubsequeri't reenergization of the relay 7, which will momentarily close the contact 7-1, actuate the latch relay 50 to reverse the position of the contact arms 51 and 59 and thereby insert the raise winding 55 into the circuit, reversing the movement of the garage door.

If any other tone frequency is received, the signal is also amplified and transmitted through the several circuits 10, 11 and 12 to the channel selection and demodulating circuit 13. The quench and other high-frequency signals are again passed over the lowest impedance path of the resonant circuit 22 and attenuated by the capacitor 27 if tone frequency is also transmitted via the low-impedance circuit 22. However, the holdoff circuit, including diode 34, rectifies a negative half cycle of such tone frequency signal, and establishes a relatively negative bias at the line 33 to cuit 14.

The present invention thus provides a highly improved garage door opener and the like, and in particular, includes a highly unique two-wire power supply for a load in a momentary circuit energization while maintaining continuous power to the control such as a receiver.

I claim:

1. A radio-control apparatus adapted to respond to a particular frequency signal with a tone frequency range for controlling a load, comprising a signal receiving and amplifying means including a superregenerative oscillator circuit having a self-quenching circuit means, an output circuit means for controlling the load, a channel selection means having a first resonant circuit in series with a high-frequency signal-attenuating circuit connected to said amplifying means to bypass essentially all signals of frequency other than the particular positively hold off the switching cirfrequency from the output circuit means, said resonant circuit including an adjustable inductance means in parallel with a capacitance means to adjust said particular frequency, a tone frequency band-pass circuit connected to said amplifying means and to said output circuit means to transmit signals of said particular frequency, a holdoff circuit connected in parallel with the attenuating circuit and between said resonant circuit and said output means, and including a rectifying means to rectify signals transmitted by said resonant circuit and directly establish a turnoff signal to the output circuit means.

2. A radio-control apparatus adapted to respond to a particular frequency signal with a tone frequency range for controlling a load, comprising a signal receiving and amplifying means including a super-regenerative oscillator circuit having a self-quenching circuit means, an output circuit means for controlling the load, a channel selection means having a first resonant circuit in series with a high-frequency signal-attenuating circuit connected to said amplifying means to bypass essentially all signals of frequency other than the particular frequency from the output circuit means, said resonant circuit including an adjustable inductance means in parallel with a capacitance means to adjust said particular frequency, a tone frequency band-pass circuit connected to said amplifying means and to said output circuit means to transmit signals of said particular frequency, said tone band-pass circuit including a rectifying means to apply a first polarity turn on signal to said output circuit means, and having a holdoff circuit connected in parallel with the attenuating circuit and between said resonant circuit and said output circuit means, said holdoff circuit including a rectifying means to apply an opposite polarity tumofi signal to said output circuit means.

3. An electrical control system having a power supply means and a pair of electrically actuated load means connected to said supply means comprising, a pair of conductors connected to said power supply means for transmitting voltage, a first series circuit connected across said conductors and including said first and second electrically actuated load means, and a rapid-acting pulsed bistable switch means connected in a second series circuit with the first of the electrically actuated load means across the conductors, and said switch means having an input means responsive to an incoming signal to rapidly energize said first load means and said switch means being reset in response to removal of the incoming signal, said input means having reset means responsive to a continuous incoming signal to reset said switch means in the presence of said signal, either resetting of said switch means providing for rapid reenergization of said first load means in response to a subsequent incoming signal to produce a rapid cyclical pulsed energization of the first load means in response to successive incoming signals while maintaining a continuous operative power to the second electrically actuated load means.

4. The electrical control system of claim 3, wherein said switch means is coupled to and'actuated by the second of said electrically actuated load means.

5. The electrical control system of claim 3, wherein said first electrically actuated load means includes an output means responsive to pulsed actuation of the first electrically actuated means, and the second electrically actuated load means is connected to the input means to actuate the rapid-acting switch means and includes an electronic switching circuit having the bias supply connected in series in said first series circuit to maintain an essentially constant bias supply to said electronic switching circuit,

6. The electrical control system of claim 3, wherein said first electrically actuated load means is a latching relay having a plurality of sequentially engaged contacts in response to sequential pulsed energization of the relay, the second of the electrically actuated means includes a radio receiving means and an electronic switching circuit including an output means connected to actuate the rapid-acting switch means, said second electrically actuated means having a power connection means connected in said first series circuit in parallel with said ra id-actin switch means.

. The e ectrrcal control system of claim 6, wherern sard and the input of the second transistor, and a resistor con-- nected across the input of the second transistor. 

1. A radio-control apparatus adapted to respond to a particular frequency signal with a tone frequency range for controlling a load, comprising a signal receiving and amplifying means including a superregenerative oscillator circuit having a selfquenching circuit means, an output circuit means for controlling the load, a channel selection means having a first resonant circuit in series with a high-frequency signal-attenuating circuit connected to said amplifying means to bypass essentially all signals of frequency other than the particular frequency from the output circuit means, said resonant circuit including an adjustable inductance means in parallel with a capacitance means to adjust said particular frequency, a tone frequency band-pass circuit connected to said amplifying means and To said output circuit means to transmit signals of said particular frequency, a holdoff circuit connected in parallel with the attenuating circuit and between said resonant circuit and said output means, and including a rectifying means to rectify signals transmitted by said resonant circuit and directly establish a turnoff signal to the output circuit means.
 2. A radio-control apparatus adapted to respond to a particular frequency signal with a tone frequency range for controlling a load, comprising a signal receiving and amplifying means including a superregenerative oscillator circuit having a self-quenching circuit means, an output circuit means for controlling the load, a channel selection means having a first resonant circuit in series with a high-frequency signal-attenuating circuit connected to said amplifying means to bypass essentially all signals of frequency other than the particular frequency from the output circuit means, said resonant circuit including an adjustable inductance means in parallel with a capacitance means to adjust said particular frequency, a tone frequency band-pass circuit connected to said amplifying means and to said output circuit means to transmit signals of said particular frequency, said tone band-pass circuit including a rectifying means to apply a first polarity turn on signal to said output circuit means, and having a holdoff circuit connected in parallel with the attenuating circuit and between said resonant circuit and said output circuit means, said holdoff circuit including a rectifying means to apply an opposite polarity turnoff signal to said output circuit means.
 3. An electrical control system having a power supply means and a pair of electrically actuated load means connected to said supply means comprising, a pair of conductors connected to said power supply means for transmitting voltage, a first series circuit connected across said conductors and including said first and second electrically actuated load means, and a rapid-acting pulsed bistable switch means connected in a second series circuit with the first of the electrically actuated load means across the conductors, and said switch means having an input means responsive to an incoming signal to rapidly energize said first load means and said switch means being reset in response to removal of the incoming signal, said input means having reset means responsive to a continuous incoming signal to reset said switch means in the presence of said signal, either resetting of said switch means providing for rapid reenergization of said first load means in response to a subsequent incoming signal to produce a rapid cyclical pulsed energization of the first load means in response to successive incoming signals while maintaining a continuous operative power to the second electrically actuated load means.
 4. The electrical control system of claim 3, wherein said switch means is coupled to and actuated by the second of said electrically actuated load means.
 5. The electrical control system of claim 3, wherein said first electrically actuated load means includes an output means responsive to pulsed actuation of the first electrically actuated means, and the second electrically actuated load means is connected to the input means to actuate the rapid-acting switch means and includes an electronic switching circuit having the bias supply connected in series in said first series circuit to maintain an essentially constant bias supply to said electronic switching circuit.
 6. The electrical control system of claim 3, wherein said first electrically actuated load means is a latching relay having a plurality of sequentially engaged contacts in response to sequential pulsed energization of the relay, the second of the electrically actuated means includes a radio receiving means and an electronic switching circuit including an output means connected to actuate the rapid-acting switch means, said second electrically actuated means having a power connection means connected in said firsT series circuit in parallel with said rapid-acting switch means.
 7. The electrical control system of claim 6, wherein said switching circuit includes a pair of cascaded electronic amplifying means interconnected by a timing capacitor to terminate conduction of the second amplifying means a predetermined time following conduction and to hold said second amplifying means off until the first electronic amplifying means ceases to conduct, whereupon said capacitor rapidly discharges to reset the switching circuit.
 8. The electrical control system of claim 7, wherein said amplifying means are complementing transistors, said capacitor being connected in series with the output of the first transistor and the input of the second transistor, and a resistor connected across the input of the second transistor. 